re: Found kitten under A/C unit, update: Mom dead, other kittens found

Judging from the pic, it's probably anywhere from4-8 weeks old. The fact that it didn't haul arse when you approached it probably means it isn't feral yet so definitely good house kitten material.
If you can, bring it in and wait to see if someone wants him. Usually kittens that size aren't "alone". Sometimes a few others from the litter will show up. However, it's possible that little guy wandered away from where mama and sibs were stashed - or it's the only survivor.

Cute cat. I got my cat 10 years ago under similar circumstances. Not sure if youve ever taken in a stray, but If you do take him in temporarily. See if he can eat solid kitten chow. Don't give him milk as it jacks up their stomachs.